We plan to utilize a human DC disease model to investigate the relationship among telomere dysfunction, the mitochondrial dysfunction, and cellular senescence. This work will be conducted in collaboration with Dr. Sharon Savage in NCI/NIH. We have selected primary skin fibroblasts isolated from patients with DC harboring germline mutations in the key telomere biology genes and age-matched healthy individuals for this study. Our initial tests have confirmed telomere defects and cellular growth retardation of DC fibroblasts. Our ongoing project investigate if sirtuin activator ameliorates mitochondrial function and telomere and cellular defects in DC cells.